Display substrate and method of manufacturing the same

Abstract

A display substrate includes a driving element, a switching element, a gate line, a data line, a driving voltage line and an electroluminescent element. The driving element includes a driving control electrode formed from a first conductive layer, and a driving input electrode and a driving output electrode formed from a second conductive layer. The switching element includes a switching control electrode formed from the second conductive layer, and a switching input electrode and a switching output electrode formed from a third conductive layer. The gate and data lines are formed from the second and third conductive layers, respectively. The driving voltage line is formed from the third conductive layer. Thus, misalignment between upper and lower patterns may be prevented to improve the reliability of a manufacturing process and increase an aperture ratio, thereby enhancing display quality.

1. A method of manufacturing a display substrate, comprising:
 successively forming a first conductive layer, an insulation interlayer and an active layer on a base substrate; 
 simultaneously patterning the active layer, the insulation interlayer and the first conductive layer to form a first active pattern, an insulation pattern and a driving control electrode; 
 forming a switching control electrode connected to a gate line, and a driving input electrode and a driving output electrode overlapping the first active pattern on the base substrate having the first active pattern, wherein the switching control electrode, the driving input electrode and the driving output electrode correspond to a second conductive layer; 
 forming a data line crossing the gate line, a switching input electrode, a switching output electrode and a driving voltage line electrically connected to the driving input electrode on the base substrate having the driving output electrode, wherein the data line, the switching input electrode, the switching output electrode and the driving voltage line correspond to a third conductive layer; and 
 forming an electroluminescent element electrically connected to the driving output electrode. 
 
     
     
       2. The method of manufacturing the display substrate of  claim 1 , prior to forming the first active pattern, the insulation pattern and the driving control electrode,
 further comprising crystallizing the active layer. 
 
     
     
       3. The method of manufacturing the display substrate of  claim 2 , wherein the active layer is crystallized by heat-treating the base substrate successively having the first conductive layer, the insulation interlayer and the active layer. 
     
     
       4. The method of manufacturing the display substrate of  claim 3 , wherein the first active pattern includes polysilicon. 
     
     
       5. The method of manufacturing the display substrate of  claim 1 , wherein forming the driving output electrode comprises forming a contact area exposing the first active pattern. 
     
     
       6. The method of manufacturing the display substrate of  claim 5 , wherein forming the driving voltage line comprises:
 forming a first insulation layer on the base substrate having the gate line, the driving input electrode and the driving output electrode; 
 removing the insulation pattern, the first active pattern and the first insulation layer to form a first contact hole in the contact area and a second contact hole on the driving input electrode; 
 forming the third conductive layer on the base substrate having the first and second contact holes; and 
 patterning the third conductive layer to form the switching output electrode making direct contact with the driving control electrode via the first contact hole and the driving voltage line making direct contact with the driving input electrode via the second contact hole. 
 
     
     
       7. The method of manufacturing the display substrate of  claim 6 , wherein forming the electroluminescent element comprises:
 forming a second insulation layer on the base substrate having the driving voltage line; 
 removing the first and second insulation layers to form a third contact hole; 
 forming an anode to make direct contact with the driving output electrode via the third contact hole; 
 forming a light-emitting layer on the anode; and 
 forming a cathode on the light-emitting layer. 
 
     
     
       8. The method of manufacturing the display substrate of  claim 7 , prior to forming the driving voltage line,
 further comprising forming a second active pattern on the first insulation layer formed on the switching control electrode. 
 
     
     
       9. The method of manufacturing the display substrate of  claim 8 , wherein the second active pattern includes amorphous silicon.